Safety device for automatic firearms



Sept. 24, 1957 E. sAETTER-LAssEN SAFETY DE-VICE FOR AUTOMATIC FIREARMSFiled April 14, 1953 Q dim@ 1 Arr/s ilnited States Patent @ffice2,807,196` Patented Sept. 24, 1957 SAFETY DEVICE FOR AUTOMATIC FIREARMSErik Saetter-Lassen, Hellerup, Denmark Application April 14, 1953,Serial No. 348,696

4 Claims. (Cl. 89-142) The invention relates to a safety device forautoma-tic firearms of the type which comprise a spring pressed recoiloperated reciprocable breech-bolt which is slidably mounted in areceiver and when the mechanism is cocked, the breech-bolt is heldretracted against the action of the recoil-spring by a spring-actuatedstop or sear which is disengageable from the breech-bolt by theoperation of the trigger. On pulling the trigger the breech-bolt will bereleased and by the action of the recoil-spring it will move forwardlyto its foremost position and fire the car- -tridge.

The present application is a continuation-in-part of my copendingapplication, Serial No. 265,865, now Patent Number 2,749,642, filedJanuary l0, 1952.

The object of the invention is to provide safety means to preventunintentional or accidental firing, for example due to an insuflicientretraction of the breech-bolt when cocking the gun, so that thebreech-bolt is not drawn back far enough to be caught by thespring-actuated stop or sear, or due to a violent mechanical shock orblow on the gun causing said sear to release the breech-bolt withoutpulling the trigger. A further object of the invention is to providemeans for automatically rendering said safety device inoperative duringfiring when the gun is manipulated in the normal and intended manner bythe operator.

These safety means may be arranged to be rendered inoperative for tiringby the operators normal two-handed grip on the gun when he is ready tore, or they may be rendered inoperative by means responsive to pullingon the trigger for firing.

To explain more clearly the nature of the invention and the way in whichit may be carried out some embodiments,

of the invention are shown in the attached drawings and will hereinafterbe described in detail.

Referring to the drawing:

Figure 1 is a longitudinal sectional view in elevation of an automaticfirearm provided with a safety device in accordance with the invention.

Figure 2 is a diagrammatic elevational view showing a modified form ofsafety pawl for use in the firearm of Fig. l.

Figure 3 is a diagrammatic elevational view showing another modifiedform of safety device for use in the firearm of Fig. 1 and which isrendered inoperative to permit tiring of the weapon by means which areresponsive to pulling on the trigger.

Referring to Fig. l, there is shown a firearm which comprises a hollowbody portion or receiver 2. A breechbolt 3 of square cross-section isslidably mounted for longitudinal reciprocation in the receiver 2, thebreechbolt 3 being shown in its foremost or tiring position. Thebreech-bolt 3 is continuously pressed forwardly by a recoil actuatedspring 4 of the helical compression type. In the receiver 2, there isdisposed a trigger mechanism comprising -a pivotally mounted trigger 5having a generally horizontally extending arm 6 arranged, upon pullingthe trigger, to press downwardly on a rearwardly extending sear 7 whichis also pivotally mounted in the receiver 2. The scar 7 is urged in acounterclockwise direction by `a leaf spring 8 so that its upper edge ispressed against the under side of the breech-bolt 3. The under side ofbreech-bolt 3 is provided with a smooth surface for engagement with theupper edge of sear 7 and a transversely extending notch 10 is formedtherein, the notch 10 having a forwardly inclined rear face 11. The sear7 is provided with a sloping rear face 12 which is engageable with therear face 11 of the notch 10 when the breech-bolt 3 is moved rearwardlyto its cocked position. When the trigger 5 is pulled, its forwardlyextending arm portion 6 will press downwardly on the sear 7 urging it ina clockwise direction so that its rear face 12 will be withdrawn fromnotch 10 and cannot reenter notch 10 until trigger 5 is released. Whentrigger 5 is held pulled, the piece will fire automatically and willcontinue to lire until trigger 5 is released or the supply of ammunitionbecomes exhausted.

In the receiver 2, there is disposed a pivotally mounted safety pawl 13located forwardly of the sear 7. The safety pawl 13 comprises arelatively thin rearwardly extending arm 14 and a downwardly extendingactuating arm 15. The arm 14 is pressed upwardly against the under sideof breech-bolt 3 by a helical torsion spring 16. As the breech-bolt 3moves forwardly from its cocked position, the rearwardly extending arm14 of safety pawl 13 is urged by torsion spring 16 to enter the notch 10in the under side of the breech-bolt 3, therebyr stopping the forwardmovement of the breech-bolt 3 and holding the breech-bolt 3 in anintermediate safety position before it can reach its foremost or firingposition and lire the next cartridge.

The receiver 2 comprises a downwardly extending ammunition magazine 17located at the forward portion of the receiver 2. When firing theWeapon, the magazine 17 is usually gripped with one hand and the trigger5 is pulled with the other hand. The downwardly extending actuating arm15 of safety pawl 13 is located in proximity to and immediately behindthe magazine 17. In gripping the magazine 17, the downwardly extendingactuating arm 15 of safety pawl 13 is pressed forwardly, holding thesafety pawl 13 rotated in a clockwise direction and preventing therearwardly extending arm 14.- from moving upwardly and entering thenotch 10 in breechbolt 3 during automatic operation of the firearm. Thesafety device is thus rendered inoperative by gripping the actuating arm15 and the weapon may be fired at will by pulling on trigger 5.

The longitudinal groove 9 formed in the under side of breech-bolt 3defines two downwardly extending spaced parallel side rails 1S on theunder side of the breech-bolt 3. The rearwardly extending arm 14 ofsafety pawl 13 is wider than the groove 9 so that its free end ispressed upwardly against the lower surfaces of the side rails 13. Thetransverse notch 1? extends completely across the under side of thebreech-bolt 3 including the side rails 18, thereby permitting the wideend of the rearwardly extending arm 14 of safety pawl 13 to enter notch1Q under the influence of torsion spring 16, unless manually restrainedby forward pressure on actuating arm 15. Within the side rails 18, thenotch 1t) is shaped to form tongues 19 which extend forwardly beyond thesloping rear face 11 of the notch 10. The sear 7 is narrower than thegroove 9 and is disposed within the groove 9 so that it clears thetongues19. The arm 14 of safety pawl 13, however, being wider than thegroove 9 will be trapped by the tongues 19 when it enters the notch 10and cannot be withdrawn solely by forward pressure on the actuating arm1S. The safety pawl 13 cannot be released until the breech-bolt 3 ispulled rearwardly by hand at least to an extent suicient to permit afree end of arm 14 to clear the tongues 19.

' Fig. 2 is a diagrammatic illustration of another form of safety pawl,the receiver being provided with a vertically movable safety pawl 35which is pressed upwardly by a helical compression .spring A,3.6 Vandis. held with its, upper beak-shapedV 'end'.Ztij'pres'sed pp against thelower surfaces of the side. rails 18 of` the breech-bolt not shown inthis, gure, so that it m-ayp'engage'pthe notch 10 4during theforwardmovement ofthe 4breech-bolt, as described above. Pawl 35'is provided'.with a forwardly projecting lug 2'1 cooperating. with a horizontalarm22of 'a safety lever 23 pivoted to the receiver, the actuating. -arm 24of which projects downwardly and isrsituated in the same position asVthe actuating. arm V previously described; In the position shown in'the drawing, pawlV 35 is heldrby theV lever `23 Vin itsV inoperative ortiring position, the actuating Varm 2 '4.being m-anually held. againstthe magazine hopper 17, and the pawl will thus notrprevent theforwardmovement of'the breech-bolt. When actuating arm 24 is releasedlever 23 will no longerV hold down safety Y pawl 35 and prevent it frommoving upwardly under the pressure of spring 36 and the safety devicewill thus prevent -accidental tiring of the gun.

Fig. 3 is a diagrammatic illustration of another embodiment of 'thesafety device in which the safety pawl engageable with the notch of thebreech-bolt is so connected with theA trigger as to be heldin its tiringor inoperative position whenever the trigger'is pulled. In this tionshown in Figure 3 the stop 29 will not prevent the turning of pawl 25,but when the slide member 30 is moved sufficiently far to the rear sothat the stop 29 is situated below the heel 28, safety pawl 25 will beprevented from turning -to its safety position under the influence oftorsion spring 27 and beak 26 will not engage lotch 10 to prevent theforward movement of the breecholt.

The actuating arm 32V of the trigger is pressed forwardly by arelatively strong helical compression spring 33 against a fixed Stop 34.The slide member 30 is pressed rearwardly by the compression spring 31,which is relatively weak, against the trigger actuating arm 32 butcannot move the trigger arm 32 rearwardly against the greater force ofthe strong compression spring 33. When trigger actuating arm 32 ispulled to re the weapon, slide member 30 is urged rearwardly by the Weakcompression spring 31, thereby moving the stop 29 beneath the heelportion 28 of safety pawl 25. Counterclockwise movement of safety pawl25 is thus prevented by stop 29 and further movement of triggeractuating arm 32 will disengage sear 7 from notch 10 to permit automaticoperation of the firearm. It should be noted in connection with Fig. 3,however, that if the sear 7 were to become disengaged from notch 10without pulling the trigger, as by the mechanical shock produced bydropping the weapon, the slide member 30 will remain in its forwardposition permitting rotation of safety pawl 25to its safetyposition andallowing its beak 26 to enter thenotch 10 and prevent accidental firingof the next cartridge.

What I claim isz Y t 1. In an automatic firearm, in combinationwithalon- Vgitudinally reciprocable breech-bolt movable between a i4 4disengaging said sear means to release said breech-bolt and permit theautomatic tiring of said' lirearm, the provision of Va safety devicecomprising: movable safety pawlV means; stop means carried by saidbreech-bolt and engageable With said safety pawl means for stoppingforward movement of saidbreech-bolt and holding said breechbolt in asafety position-intermediate said cocked position and said tiringposition; resilient means urging said safety pawl means toward aposition in which it will engage said stop means Vupon forward movement.of said breech-bolt from said cocked position; a movable stop membercooperating with said trigger means for movement therewith, and meanscarried by said safety pawl means and engageable with said movable stopmember for holding t said safety pawl means against the action of saidresilient means and preventing movement of said safety pawl means tosaidstop meansengaging position upon movement Vcf'said stop member',accompanying iiring operation of said trigger'meansj Y 2. In anautomatic firearm, in combination with aV Iongitudi'nall'y reciprocablebreech-bolt having a notch formed therein, 'said breech bolt beingmovable'between a rearwardly disposedcocked position:y and a foremostfiring po- Y sition; recoil Aactuated Spring means yieldingly urgingsaid breech-bolt forwardly. toward saidV iring'position; spring pressedsear means-movable into said notch to engage said bree'ch-bolt and holdsaid breech-bolt'in said cocked position; and manually operable triggermeans for moving said sear'means. out of Ysaid notch to release saidbreech-bolt and permitV automatic Vfiring of saidirearm, the provisionof' a safety device comprising: asafety pawl member disposed' forwardlyof saidV sear means and pivotally mounted for rotation about an axisextending transversely below saidY breech-bolt, said safety pawl membercomprising a rearwardly directed tip portion adaptedV to enter saidnotch and stop forward p movement of said breech-bolt` and hold said.breech-bolt in a safety positioninterinedi'ate said cocked position andsaid tiring position; resilient means urging said tip portion of saidsafety pawl member toward' said breech-bolt to enter said notch; alongitudinally movable slide member having a stop portion, said slidemember cooperating with said trigger means for movement therewith, saidsafety pawl member comprising a. portion engageable with said stopportion'of said slide member'to preventmovement of said tipportion ofsaid pawl. member toenter said notch upon longitudinal movement of saidslide member accompanying. tiring operation ofsaid trigger means.

3. The combination according to claim 2, in which the underside ofsaidbreech-bolt has a centralY longitudinal groove formedthereint'deiini'ng spaced v.downwardly extending side rails, said searmeans being narrower than the space between said railsl and beingdisposed therebetween, saidi notch being formed in the under side ofsaid breech-bolt and extending Vtransversely acrossthe entire under sidethereof including said side rails, and wherein said tip portion of saidsafety pawl member is widery than Vsaid groove, said tip` portion beingurged by said resilient means toward said-side rails for entry into saidnotchV to stop and holdl said breech-bolt in said safety position, theportion of said notch which is. formed in said side rails beingshaped toprovide forwardly extending portions for trapping s'aicl tip portion ofVsaid safety pawl member therein until said breech-boltis drawnrearwardly from said safety position againsty the action of said recoilactuated spring means, and thel central portion of saidl notchintermediate said side rails vbeing shaped to permit'withdrawal of,said. Sear ymeans from said notch solely by operation offsaid' triggermeans.

. 4. The. combination |according toclaim 2, wherein said trigger means`comprises a surface which moves rearward'- ly upon'ringoperation ofsaidf trigger means, said combination furthercompri'sing spring meansurging said:slide` member. rearwardly into engagement with saidysurface, saidstop' portion of said slidemember being positioned forengagement by said tip movement preventing portion 981,210 of saidsafety pawl member in response to rearward move- 1,695,508 ment of saidslide member accompanying said rearward 2,169,084 movement of saidsurface. 2,608,136

5 References Cited in the file of this patent UNITED STATES PATENTS62u32 938,349 Tambour Oct. 26, 1909 6 Menteyne et a1 Jan. 10, 1911Skinner et a1. De. 18, 1928 Swartz Aug. s, 1939 Guisasola Aug. 26, 1952FOREIGN PATENTS Denmark Oct. 11, 1948 Great Britain Oct. 29, 1952

